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Subrata Ghosh - One of the best experts on this subject based on the ideXlab platform.
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at the molecular level through photophysical studies structural implications on the reactivity of dual site sensitive positional isomers toward a gasotransmitter h2s
Journal of Physical Chemistry C, 2015Co-Authors: M Venkateswarulu, Pankaj Gaur, Sougata Sinha, Avijit Pramanik, Subrata GhoshAbstract:A combined experimental and theoretical approach has enabled us to understand at the molecular level the importance of positional and electronic effects of chemical Functionality Present in molecular system that acts as an optical signaling agent. The Present study demonstrates the structural implications of isomeric dual-site reactive (nitro and sulfonte ester groups) molecular probes (P1, P2, and P3) on optical signaling of hydrogen sulfide (H2S), a known emerging mediator in human physiological activities and diseases. The reactivity of these probes toward H2S was established using fluorescence signaling studies. The reductive interaction of H2S with nitro Functionality of P2 resulted in the formation of orange fluorescent amine derivative P2′, while the nucleophilic S–O bond cleavage of sulfonate ester group of P3 produced sulfonothionic acid derivative P3′ as a green emissive fluorescent species. Crystal structure determination and structure–reactivity relationship studies demonstrated positional as ...
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At the Molecular Level through Photophysical Studies: Structural Implications on the Reactivity of Dual-Site Sensitive Positional Isomers Toward a Gasotransmitter (H2S)
2015Co-Authors: M Venkateswarulu, Pankaj Gaur, Sougata Sinha, Avijit Pramanik, Subrata GhoshAbstract:A combined experimental and theoretical approach has enabled us to understand at the molecular level the importance of positional and electronic effects of chemical Functionality Present in molecular system that acts as an optical signaling agent. The Present study demonstrates the structural implications of isomeric dual-site reactive (nitro and sulfonte ester groups) molecular probes (P1, P2, and P3) on optical signaling of hydrogen sulfide (H2S), a known emerging mediator in human physiological activities and diseases. The reactivity of these probes toward H2S was established using fluorescence signaling studies. The reductive interaction of H2S with nitro Functionality of P2 resulted in the formation of orange fluorescent amine derivative P2′, while the nucleophilic S–O bond cleavage of sulfonate ester group of P3 produced sulfonothionic acid derivative P3′ as a green emissive fluorescent species. Crystal structure determination and structure–reactivity relationship studies demonstrated positional as well as electronic effects of nitro Functionality on the reactivity of these probes. While the electronic effect is responsible for increasing the reactivity of sulfonate Functionality, the accessibility of the reactive site by H2S is dictated by the steric factor. Although both −M (mesomeric) and −I (inductive) effects of nitro Functionality are supposed to be prominent in P1 and P3, crystal structure analysis revealed a steric crowding on P1created by nitro group as well as out-of-plane arrangement of nitro group, which in turn makes P1 much less reactive than P3. In the case of P2, the probe is free from steric effect, but the weak −I effect and the absence of −M effect made sulfonate Functionality nonreactive toward H2S. At the same time, slow reductive interaction of nitro group of P2 yielded orange emissive fluorescent species P2′
Ladewig B - One of the best experts on this subject based on the ideXlab platform.
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Polymer-assisted modification of metal-organic framework MIL-96 (Al): influence of HPAM concentration on particle size, crystal morphology and removal of harmful environmental pollutant PFOA
'Elsevier BV', 2020Co-Authors: Lh ,mohd Azmi, Williams D, Ladewig BAbstract:A new synthesis method was developed to prepare an aluminum-based metal organic framework (MIL-96) with a larger particle size and different crystal habits. A low cost and water-soluble polymer, hydrolyzed polyacrylamide (HPAM), was added in varying quantities into the synthesis reaction to achieve >200% particle size enlargement with controlled crystal morphology. The modified adsorbent, MIL-96-RHPAM2, was systematically characterized by SEM, XRD, FTIR, BET and TGA-MS. Using activated carbon (AC) as a reference adsorbent, the effectiveness of MIL-96-RHPAM2 for perfluorooctanoic acid (PFOA) removal from water was examined. The study confirms stable morphology of hydrated MIL-96-RHPAM2 particles as well as a superior PFOA adsorption capacity (340 mg/g) despite its lower surface area, relative to standard MIL-96. MIL-96-RHPAM2 suffers from slow adsorption kinetics as the modification significantly blocks pore access. The strong adsorption of PFOA by MIL-96-RHPAM2 was associated with the formation of electrostatic bonds between the anionic carboxylate of PFOA and the amine Functionality Present in the HPAM backbone. Thus, the strongly held PFOA molecules in the pores of MIL-96-RHPAM2 were not easily desorbed even after eluted with a high ionic strength solvent (500 mM NaCl). Nevertheless, this simple HPAM addition strategy can still chart promising pathways to impart judicious control over adsorbent particle size and crystal shapes while the introduction of amine Functionality onto the surface chemistry is simultaneously useful for enhanced PFOA removal from contaminated aqueous systems
Bp Ladewig - One of the best experts on this subject based on the ideXlab platform.
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Polymer-assisted modification of metal-organic framework MIL-96 (Al): influence on particle size, crystal morphology and perfluorooctanoic acid (PFOA) removal
'American Chemical Society (ACS)', 2020Co-Authors: Hakim Mohd Azmi L, Williams D, Bp LadewigAbstract:A new synthesis method was developed to prepare an aluminum-based metal organic framework (MIL-96) with a larger particle size and different crystal habits. A low cost and water-soluble polymer, hydrolyzed polyacrylamide (HPAM), was added in varying quantities into the synthesis reaction to achieve >200% particle size enlargement with controlled crystal morphology. The modified adsorbent, MIL-96-RHPAM2, was systematically characterized by SEM, XRD, FTIR, BET and TGA-MS. Using activated carbon (AC) as a reference adsorbent, the effectiveness of MIL-96-RHPAM2 for perfluorooctanoic acid (PFOA) removal from water was examined. The study confirms stable morphology of hydrated MIL-96-RHPAM2 particles as well as a superior PFOA adsorption capacity (340 mg/g) despite its lower surface area, relative to standard MIL-96. MIL-96-RHPAM2 suffers from slow adsorption kinetics as the modification significantly blocks pore access. The strong adsorption of PFOA by MIL-96-RHPAM2 was associated with the formation of electrostatic bonds between the anionic carboxylate of PFOA and the amine Functionality Present in the HPAM backbone. Thus, the strongly held PFOA molecules in the pores of MIL-96-RHPAM2 were not easily desorbed even after eluted with a high ionic strength solvent (500 mM NaCl). Nevertheless, this simple HPAM addition strategy can still chart promising pathways to impart judicious control over adsorbent particle size and crystal shapes while the introduction of amine Functionality onto the surface chemistry is simultaneously useful for enhanced PFOA removal from contaminated aqueous systems.A new synthesis method was developed to prepare an aluminum-based metal organic framework (MIL-96) with a larger particle size and different crystal habits. A low cost and water-soluble polymer, hydrolyzed polyacrylamide (HPAM), was added in varying quantities into the synthesis reaction to achieve >200% particle size enlargement with controlled crystal morphology. The modified adsorbent, MIL-96-RHPAM2, was systematically characterized by SEM, XRD, FTIR, BET and TGA-MS. Using activated carbon (AC) as a reference adsorbent, the effectiveness of MIL-96-RHPAM2 for perfluorooctanoic acid (PFOA) removal from water was examined. The study confirms stable morphology of hydrated MIL-96-RHPAM2 particles as well as a superior PFOA adsorption capacity (340 mg/g) despite its lower surface area, relative to standard MIL-96. MIL-96-RHPAM2 suffers from slow adsorption kinetics as the modification significantly blocks pore access. The strong adsorption of PFOA by MIL-96-RHPAM2 was associated with the formation of electrostatic bonds between the anionic carboxylate of PFOA and the amine Functionality Present in the HPAM backbone. Thus, the strongly held PFOA molecules in the pores of MIL-96-RHPAM2 were not easily desorbed even after eluted with a high ionic strength solvent (500 mM NaCl). Nevertheless, this simple HPAM addition strategy can still chart promising pathways to impart judicious control over adsorbent particle size and crystal shapes while the introduction of amine Functionality onto the surface chemistry is simultaneously useful for enhanced PFOA removal from contaminated aqueous systems.
Williams D - One of the best experts on this subject based on the ideXlab platform.
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Polymer-assisted modification of metal-organic framework MIL-96 (Al): influence on particle size, crystal morphology and perfluorooctanoic acid (PFOA) removal
'American Chemical Society (ACS)', 2020Co-Authors: Hakim Mohd Azmi L, Williams D, Bp LadewigAbstract:A new synthesis method was developed to prepare an aluminum-based metal organic framework (MIL-96) with a larger particle size and different crystal habits. A low cost and water-soluble polymer, hydrolyzed polyacrylamide (HPAM), was added in varying quantities into the synthesis reaction to achieve >200% particle size enlargement with controlled crystal morphology. The modified adsorbent, MIL-96-RHPAM2, was systematically characterized by SEM, XRD, FTIR, BET and TGA-MS. Using activated carbon (AC) as a reference adsorbent, the effectiveness of MIL-96-RHPAM2 for perfluorooctanoic acid (PFOA) removal from water was examined. The study confirms stable morphology of hydrated MIL-96-RHPAM2 particles as well as a superior PFOA adsorption capacity (340 mg/g) despite its lower surface area, relative to standard MIL-96. MIL-96-RHPAM2 suffers from slow adsorption kinetics as the modification significantly blocks pore access. The strong adsorption of PFOA by MIL-96-RHPAM2 was associated with the formation of electrostatic bonds between the anionic carboxylate of PFOA and the amine Functionality Present in the HPAM backbone. Thus, the strongly held PFOA molecules in the pores of MIL-96-RHPAM2 were not easily desorbed even after eluted with a high ionic strength solvent (500 mM NaCl). Nevertheless, this simple HPAM addition strategy can still chart promising pathways to impart judicious control over adsorbent particle size and crystal shapes while the introduction of amine Functionality onto the surface chemistry is simultaneously useful for enhanced PFOA removal from contaminated aqueous systems.A new synthesis method was developed to prepare an aluminum-based metal organic framework (MIL-96) with a larger particle size and different crystal habits. A low cost and water-soluble polymer, hydrolyzed polyacrylamide (HPAM), was added in varying quantities into the synthesis reaction to achieve >200% particle size enlargement with controlled crystal morphology. The modified adsorbent, MIL-96-RHPAM2, was systematically characterized by SEM, XRD, FTIR, BET and TGA-MS. Using activated carbon (AC) as a reference adsorbent, the effectiveness of MIL-96-RHPAM2 for perfluorooctanoic acid (PFOA) removal from water was examined. The study confirms stable morphology of hydrated MIL-96-RHPAM2 particles as well as a superior PFOA adsorption capacity (340 mg/g) despite its lower surface area, relative to standard MIL-96. MIL-96-RHPAM2 suffers from slow adsorption kinetics as the modification significantly blocks pore access. The strong adsorption of PFOA by MIL-96-RHPAM2 was associated with the formation of electrostatic bonds between the anionic carboxylate of PFOA and the amine Functionality Present in the HPAM backbone. Thus, the strongly held PFOA molecules in the pores of MIL-96-RHPAM2 were not easily desorbed even after eluted with a high ionic strength solvent (500 mM NaCl). Nevertheless, this simple HPAM addition strategy can still chart promising pathways to impart judicious control over adsorbent particle size and crystal shapes while the introduction of amine Functionality onto the surface chemistry is simultaneously useful for enhanced PFOA removal from contaminated aqueous systems.
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Polymer-assisted modification of metal-organic framework MIL-96 (Al): influence of HPAM concentration on particle size, crystal morphology and removal of harmful environmental pollutant PFOA
'Elsevier BV', 2020Co-Authors: Lh ,mohd Azmi, Williams D, Ladewig BAbstract:A new synthesis method was developed to prepare an aluminum-based metal organic framework (MIL-96) with a larger particle size and different crystal habits. A low cost and water-soluble polymer, hydrolyzed polyacrylamide (HPAM), was added in varying quantities into the synthesis reaction to achieve >200% particle size enlargement with controlled crystal morphology. The modified adsorbent, MIL-96-RHPAM2, was systematically characterized by SEM, XRD, FTIR, BET and TGA-MS. Using activated carbon (AC) as a reference adsorbent, the effectiveness of MIL-96-RHPAM2 for perfluorooctanoic acid (PFOA) removal from water was examined. The study confirms stable morphology of hydrated MIL-96-RHPAM2 particles as well as a superior PFOA adsorption capacity (340 mg/g) despite its lower surface area, relative to standard MIL-96. MIL-96-RHPAM2 suffers from slow adsorption kinetics as the modification significantly blocks pore access. The strong adsorption of PFOA by MIL-96-RHPAM2 was associated with the formation of electrostatic bonds between the anionic carboxylate of PFOA and the amine Functionality Present in the HPAM backbone. Thus, the strongly held PFOA molecules in the pores of MIL-96-RHPAM2 were not easily desorbed even after eluted with a high ionic strength solvent (500 mM NaCl). Nevertheless, this simple HPAM addition strategy can still chart promising pathways to impart judicious control over adsorbent particle size and crystal shapes while the introduction of amine Functionality onto the surface chemistry is simultaneously useful for enhanced PFOA removal from contaminated aqueous systems
M Venkateswarulu - One of the best experts on this subject based on the ideXlab platform.
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at the molecular level through photophysical studies structural implications on the reactivity of dual site sensitive positional isomers toward a gasotransmitter h2s
Journal of Physical Chemistry C, 2015Co-Authors: M Venkateswarulu, Pankaj Gaur, Sougata Sinha, Avijit Pramanik, Subrata GhoshAbstract:A combined experimental and theoretical approach has enabled us to understand at the molecular level the importance of positional and electronic effects of chemical Functionality Present in molecular system that acts as an optical signaling agent. The Present study demonstrates the structural implications of isomeric dual-site reactive (nitro and sulfonte ester groups) molecular probes (P1, P2, and P3) on optical signaling of hydrogen sulfide (H2S), a known emerging mediator in human physiological activities and diseases. The reactivity of these probes toward H2S was established using fluorescence signaling studies. The reductive interaction of H2S with nitro Functionality of P2 resulted in the formation of orange fluorescent amine derivative P2′, while the nucleophilic S–O bond cleavage of sulfonate ester group of P3 produced sulfonothionic acid derivative P3′ as a green emissive fluorescent species. Crystal structure determination and structure–reactivity relationship studies demonstrated positional as ...
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At the Molecular Level through Photophysical Studies: Structural Implications on the Reactivity of Dual-Site Sensitive Positional Isomers Toward a Gasotransmitter (H2S)
2015Co-Authors: M Venkateswarulu, Pankaj Gaur, Sougata Sinha, Avijit Pramanik, Subrata GhoshAbstract:A combined experimental and theoretical approach has enabled us to understand at the molecular level the importance of positional and electronic effects of chemical Functionality Present in molecular system that acts as an optical signaling agent. The Present study demonstrates the structural implications of isomeric dual-site reactive (nitro and sulfonte ester groups) molecular probes (P1, P2, and P3) on optical signaling of hydrogen sulfide (H2S), a known emerging mediator in human physiological activities and diseases. The reactivity of these probes toward H2S was established using fluorescence signaling studies. The reductive interaction of H2S with nitro Functionality of P2 resulted in the formation of orange fluorescent amine derivative P2′, while the nucleophilic S–O bond cleavage of sulfonate ester group of P3 produced sulfonothionic acid derivative P3′ as a green emissive fluorescent species. Crystal structure determination and structure–reactivity relationship studies demonstrated positional as well as electronic effects of nitro Functionality on the reactivity of these probes. While the electronic effect is responsible for increasing the reactivity of sulfonate Functionality, the accessibility of the reactive site by H2S is dictated by the steric factor. Although both −M (mesomeric) and −I (inductive) effects of nitro Functionality are supposed to be prominent in P1 and P3, crystal structure analysis revealed a steric crowding on P1created by nitro group as well as out-of-plane arrangement of nitro group, which in turn makes P1 much less reactive than P3. In the case of P2, the probe is free from steric effect, but the weak −I effect and the absence of −M effect made sulfonate Functionality nonreactive toward H2S. At the same time, slow reductive interaction of nitro group of P2 yielded orange emissive fluorescent species P2′
